The present invention relates to compositions and methods of providing rapid and persistent control of a broad-spectrum of microbes on mammalian surfaces by topical application of compositions.
Lameness of diary cows and sheep is one of the major problems facing the dairy and meat industry, respectively, today. The cost of lameness is measured by lost milk production, culled cows, underweight meat animals, additional labor, veterinary bills, and medicines for treatment. In the United States, the annual overall cost of lameness is estimated to exceed 570 million dollars. It is especially a problem in large herds, which are the fastest growing segment of the market. The prevalence of lameness in large herds is 50% or more.
Lameness is, in many cases, caused by anaerobic organisms such as Arcanobacterium pyogenes (previously called Corynebacterium pyogenes), in particular where the infection goes into the deep structure of the hoof. In sheep the infection may be accompanied by swelling and a white to black pus discharge.
There are multiple causes for lameness ranging from lack of general stable hygiene, specific hoof hygiene, hoof care, malnutrition, general genetic disposition, specific genetic defects to bacterial and viral infections. For example, fibroma (corns) is a genetic condition found in cattle which causes a hard, fibrous lump to form between the claws of the foot. The corn makes the hoof more susceptible to subsequent bacterial and viral infections. These infections occur at various locations in and around the hooves of the cattle.
In addition to the general lesions caused by infection, a disease of unknown etiology has been spreading throughout the western United States. This disease is digital dermatitis. Digital dermatitis is characterized by painful lesions, which often are surrounded by a ridge of hyperkeratotic (thickened) skin with finger like projections. Due to its appearance, the disease is commonly referred to as hairy wart or strawberry disease; it is also known as Mortellaro disease.
Studies have shown that a third of all lameness in cows is caused by digital dermatitis. Digital dermatitis is present worldwide and is estimated to be present in 41% of herds smaller than 100 cows, and from 64% to 82% in larger herds.
Other contagious and debilitating diseases of the bovine foot and hoof include such conditions as bovine hoof rot and interdigital dermatitis. In addition to causing lameness in diary cows, these contagious diseases also cause a significant decrease in milk production and sometimes death. Dairy farmers report as much as 50% less milk being produced per cow. (Linda Leake, Farm Journal, Inc., (1998).) In sheep, in addition to causing lameness and reduced production, foot rot is highly contagious sometimes resulting in a whole flock becoming infected. (Government of Newfoundland and Labarador 2004)
For years, directing animals through hoof baths containing hoof care solutions has been practiced as an aid to general hoof health; and hygiene for the prevention of, and a cure for, diseases of the animals' hooves. Materials used for these solutions include copper sulfate, zinc sulfate, formaldehyde, quaternary ammonium compounds, peroxides, organic acids, and their combinations, and certain antibiotics. Additionally, several over the counter commercially compounded liquid products have been and are being used. Major manufacturers of this latter category are Delaval (DoubleAction), Westfalia-Surge (Pedicure Rx), and SSI Corporation (Healthy Foot). Copper sulfate, zinc sulfate and other heavy metal based antimicrobials are usually applied in 5% to 10% solutions to be effective.
Recently, the negative environmental impact of the use of heavy metal compounds has been recognized. Efforts have been made to use mixed salts in combination with specific additives in order to reduce the overall use of heavy metal (to concentrations as low as low as 0.5%). However, despite regulatory restrictions, heavy metals are still in use since no effective alternative products are presently on the market.
Hoof baths are generally located in the return alley of dairy milking barns or parlors. After being milked, the animals typically walk through the hoof bath on the way back to where they are housed. The feet and hooves will typically contain accumulated dirt and manure. This is especially true in modern dairy facilities with housing contained in limited areas such as free stall or tie stall barns or dry lots instead of open pasture.
In addition, on passing through the hoof bath, the cows may defecate into the hoof bath. The added organic material or load to the hoof bath compromises the antimicrobial products' ability to work in the disinfection and cleansing of the cow hooves where the causative microorganisms are located. For economic reasons, the use of antibacterial chemical and biological products in doses high enough to compensate for the organic material present in the hoof bath and to penetrate through organic material and whatever tissue may conceal or otherwise harbor the bacterial pathogens, is usually cost prohibitive. Other chemical products that are less expensive to use at higher doses have the disadvantage in that they may be toxic to the animals, to the people working in the dairy facilities, and, particularly, to the environment. Heavy metal moieties of the compounds do not break down and accumulate in the environment.
Accordingly, there is a need for a more effective and environmentally friendly manner by which to treat and prevent hoof diseases in bovine livestock. In particular, a need exists for an effective method to control a broad spectrum of microbes that is fast-acting, has long-lasting efficacy, and is mild to livestock.